Traditional fixed-wing aircraft generally require long runways or launching systems to provide a distance for the aircraft to build sufficient speed to generate lift for flight. And runways are generally required for fixed-wing aircraft to land. Some aircraft, such as tailsitter aircraft and rotorcraft (including multirotor aircraft), avoid a need for horizontal space for take-off and landing by taking off and landing vertically. Tailsitter aircraft generally take off from (and land on) their tails, pitching between vertical and horizontal orientations for flight in midair.
But rotorcraft are not optimal for efficient horizontal flight because the rotor(s) must provide both lift and forward thrust. And tailsitter aircraft can be prone to tipping when landing or taking off in a vertical configuration due to a high center of gravity. A wide landing base is required to prevent the tailsitter from tipping over, especially when landing or taking off in windy conditions or from uneven ground.
Existing tailsitter aircraft may include a wide landing base or landing legs in the form of large vertical tails or fins. But such large tails or fins are not necessary for horizontal flight, so they reduce performance by increasing drag and weight. And some existing tailsitter aircraft may have large, retractable landing legs but these legs also require unnecessary increases to aircraft weight. Accordingly, existing tailsitter aircraft sacrifice performance (such as weight or aerodynamic qualities) in order to provide landing and ground stability.